In Japanese Laid-Open Patent Publication No. 10-198433, the present applicant has proposed a pressure reducing apparatus through which a pressure fluid supplied from a first side is reduced in pressure to a desired pressure and guided out to a second side. In the case that the pressure fluid is supplied at a desired set pressure from a fluid pressure supply source to a fluid pressure device, the pressure reducing apparatus is disposed between the fluid pressure supply source and the fluid pressure device, whereby the pressure fluid, which is supplied to the first side from the pressure fluid supply source, is reduced in pressure to a desired pressure corresponding to specifications of the fluid pressure device that is connected to the second side, and thereafter, the pressure fluid is supplied to the second side.